package com.company;

public class Main26 {
    public static void main(String[] args) {
        float x=2,y=1,c = x / y,z=0;;
        for (int i=2;i<=20;i++){
            z=y;
            y=x;
            x=x+z;

            c+= x/y;

        }
        System.out.println(c);
    }
}
